Mo-Catalyzed Direct Nitrogen-to-Amine Conversion in Flow via Active N-H Species.

Area of Science:

• Catalysis
• Chemical Engineering
• Materials Science

Background:

• Direct conversion of N₂ to valuable nitrogen-containing chemicals (NCCs) is highly desirable but faces thermodynamic challenges.
• Conventional methods often rely on ammonia (NH₃) or strong reductants, limiting efficiency and scalability.

Purpose of the Study:

• To develop an efficient and scalable method for direct N₂-to-amine conversion.
• To utilize molybdenum-based catalysts and alcohols for amine synthesis without involving NH₃.

Main Methods:

• Employed a scalable flow system with commercial Mo, MoO₂, and MoO₃ catalysts.
• Utilized various alcohols (MeOH, EtOH, n-PrOH) as reactants.
• Conducted mechanistic studies to elucidate reaction pathways.

Main Results:

• Achieved direct N₂-to-amine conversion with high efficiency (>95% conversion at 225 °C).
• Demonstrated low-temperature activity, reducing operating temperatures by ~100 °C compared to industrial mordenite (MOR) catalysts.
• Identified NH_x species as key intermediates in a sequential nitrogen hydrogenation and alkylation pathway.

Conclusions:

• N-H species on Mo-based catalysts enable efficient direct N₂-to-amine conversion.
• The developed flow system offers a practical and scalable route for amine synthesis, bypassing NH₃.
• This strategy represents a significant advancement in N₂ utilization for chemical production.